Over the last two decades there has been a significant increase in the presence of motorized rail transportation in urban areas resulting in an increasing need for methods of reducing the high frequency sounds which result from the twisting of the axle and sudden subsequent release of the twist as a curved rail is negotiated by the wheels of a train.
Much of the present technology developed to reduce this noise and generally lubricate the contact between train wheels and railway track has been to pump oil under pressure through nozzles directed at the wheel contact point with the track. Such technology leaves oil on the track and surrounding area, the latter being of environmental concern. Due to this concern the United States Environmental Protection Agency has indicated that this type of technology will be phased out.
Recently, solid stick lubricants have increased in popularity and have been useful for reducing friction and otherwise varying the frictional characteristics of steel to steel contact between train wheels and railway tracks. Although a lubricating device for applying lubricant to the inner side of outer railroad curves has been disclosed as a means of reducing the friction (U.S. Pat. No. 1,820,815--Maney), in a typical application, a stick lubricant is applied by a holding means to the wheel flange and/or tread of a train.
The stick lubricants have generally been applied to the wheel by a pushing mechanism contained in a device which holds a stick in position. The spring loaded applicator stick system as taught in U.S. Pat. No. 5,054,582 by Aracil is one such device.
The concept of a self controlling lubricating system mounted to the vehicle as designed for rail cars is well known and has been disclosed at least as early as 1910 (Canadian Patent No. 156,866--Conniff). Others in that time period include Canadian Patent No. 163,700--Gerlinger and Canadian Patent No. 167,026--Miner.
A number of other lubricator stick assembly systems subsequently disclosed in the art include U.S. Pat. No. 1,780,464--Coppage; U.S. Pat. No. 2,866,521--Gibson; U.S. Pat. No. 2,727,589--Capney; U.S. Pat. No. 2,589,582--Strugghold; U.S. Pat. No. 2,326,000--Teeple; U.S. Pat. No. 1,185,682--Kirkegard; and U.S. Pat. No. 1,102,473--Chappell, the most recent being that of AraCil (U.S. Pat. No. 5,054,582).
Most locomotives are serviced at approximately 92 day intervals or after approximately 40,000 to 60,000 miles of travel. Currently, a single lubricant stick lasts on average for approximately 15,000 miles of travel. Space limitations restrict the stick length that can be applied to the wheel. Consequently, there is a need for providing longer lasting lubricating.
There is a general lack of space on locomotives and rolling stock in the area of the inside center line of the wheels where the lubrication is most advantageously applied. Tube assemblies, step ladders, storage tanks, etc. all vie for space in this area. Lengthening the stick lubricant is therefore impractical.